The present invention relates to the field of cooling engineering and busbar engineering. It relates to a cooling device for an electronic component and a cooling system with such cooling devices according to the preamble of the independent claims.
Cooling devices for electronic components, in particular for power semiconductor modules, are currently used in a plethora of electronic power circuits. It is usual for a cooling fluid, which flows through the cooling device, to dissipate excess thermal energy from the electronic component to be cooled.
In WO 00/21131, a cooling device suitable for the cooling of an electronic component is disclosed. In this document, the cooling device is built up from profiled plates stacked and lying on one another, the profiled plates being connected to one another. The profile of the profiled plates is configured in such a way that cooling channels are formed in the stack as a result of the profiled plates being stacked. In order to supply a cooling fluid, cooling fluid connections are arranged at right angles to the stacking direction and extend into some of the cooling channels.
Furthermore, the stack of profiled plates of the cooling device from WO 00/21131 is closed off in the stacking direction by termination plates. One of the termination plates is designed as a mounting plate. This mounting plate is used to make extensive contact with the electronic component to be cooled in order to carry heat away to the cooling device. Furthermore, the making of extensive contacts permits an electrical connection, in particular to carry current to or from the electronic component to be cooled. The electrical connection from the mounting plate to a power busbar system is provided via a screw connection.
The problem with the cooling device according to WO 00/21131 is that the electrical connection by means of the screw connection between mounting plate and the power busbar system represents a highly inductive design, as a result of which, in the case of large current changes, high voltages are induced, which can destroy the electronic component to be cooled. Furthermore, mechanical effects which occur on the power busbar system are passed on virtually undamped to the mounting plate connected via the screw connection, so that the electronic component can be damaged or tears off the mounting plate. Furthermore, the screw connection has a high contact resistance, which gives rise to high electrical losses. In addition, such a screw connection requires a great deal of mounting and needs an appropriate amount of space for the mounting and for the accessibility for inspection purposes, so that high costs also arise.
Furthermore, a cooling system, which has two cooling devices, is specified in WO 00/21131. A first cooling device is connected on one side, by its mounting plate and by means of a screw connection, to a power busbar system, so that an electrical connection is produced. On the other side, the first cooling device is likewise connected, by means of a screw connection, to the electric component to be cooled. A second cooling device is connected, both thermally and electrically conductively, to the first cooling device via the component to be cooled and an intermediate busbar system. For this purpose, the second cooling device is pressed against the intermediate busbar system by means of the application of force. The application of force also has the effect that the intermediate busbar system is pressed against the electric component to be cooled.
The above-described cooling system from WO00/21131 is particularly susceptible to mechanical vibrations, which can have the effect of slipping and/or fracture of the second cooling device and/or the intermediate busbar system. As a result, however, the making of thermal contact, to be ensured for adequate heat dissipation, between the second cooling device and the electronic component to be cooled can no longer be achieved via the intermediate busbar system. In addition, the making of electric contact between the two cooling devices via the electronic component to be cooled and the intermediate busbar system is no longer ensured, as a result of the aforementioned slipping. This can lead to partial discharges, as a result of which the electronic component can be destroyed.
It is therefore an object of the invention to design a cooling device for an electronic component which is distinguished by a low inductance and, at the same time, is flexible in relation to mechanical effects and has a construction which is easy to mount and space-saving and therefore cost-effective. Furthermore, a cooling system is to be specified which comprises the cooling devices according to the invention and has a rugged and vibration-resistant construction with respect to mechanical effects. These objects are achieved by the features of claim 1 and 12. Advantageous developments of the invention are specified in the subclaims.
The cooling device according to the invention for an electronic component is built up from a stack of profiled plates lying on one another and connected to one another. At the end of the stack, termination plates are provided in the stacking direction, at least one of the termination plates being designed to make extensive contact, both thermal and electrical, with the electric component. According to the invention, at least one of the profiled plates has a flexible extension which projects beyond the cross section of the stack. By means of this flexible extension, a particularly low-inductance possible connection is provided, for example to a power busbar system, so that the risk of the destruction of the electronic component to be cooled, as a result of high induced voltages, can be minimized. With the aid of the flexible extension, mechanical effects, in particular shaking movements or mechanical vibrations, are advantageously kept away from the making of contact between the component to be cooled on the termination plate, and therefore from the component itself, so that even severe mechanical effects on the flexible extension have virtually no mechanical effect on the stack of profiled plates, on the termination plates and on the component. The cooling device according to the invention is additionally built up very simply, in a space-saving and easy-to-mount manner, in particular in the event of replacement of the electronic component, since there are no screw connections requiring a great deal of mounting and maintenance, as disclosed by the prior art, so that in addition a cost-effective construction is achieved.
In the cooling system according to the invention, at least one flexible extension of a first cooling device is connected to at least a second cooling device. By means of this connection, a particularly rugged construction of the cooling system according to the invention is achieved, which is primarily distinguished with respect to mechanical effects. As a result, such effects are kept away to the greatest possible extent from the respective electronic component associated with each cooling device, so that even under extreme mechanical effects, the making of thermal and electrical contact with the respective electronic component on the associated termination plate can be ensured.
This and further objects, advantages and features of the present invention will become obvious from the following detailed description of preferred exemplary embodiments of the invention, in conjunction with the drawing.